Clipping chickens wings

I discovered today that one of my favorite chickens is an escape artist, and has mastered flying on top of our leanto (in the background by the fly trap) and down to get to the grass in our backyard. Which wouldn't bother me, but my parents don't want them there and I'm not sure that all of the plants in our back yard are non-toxic to chickens. My Dad is talking clipping one of her wings to stop her.

I don't have any strong feelings about wing clipping at this time (my Dad's done it before and done an ok job). However I know that some people do and was wondering if you could help me understand why before we do that? Also, I was wondering if we should clip the wings of the other two also (They all three like to fly up on top of the henhouse. If one of them was no longer able to, that might put her at a disadvantage?).

Also, if you have any ideas of fixes (Aviary netting maybe), I would be glad to consider those.

Thanks. My Dad put up some chicken wire and hardware cloth today to raise the height of our fence/leanto. If that doesn't work, then we might have to try the wing clipping. I was worried it might cause issues (such as with their feathers growing back in) that I didn't know about. We gave them the run of the backyard today, which they enjoyed.